<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>CSS选择器</title>
    <style>
        .test1{
            color: red;
        }
        .test1{
            color: blue;
        }
        .test2{
            color: red!important;
        }
        .test2{
            color: blue;
        }
        #test3{
            color: red;
        }
    </style>
</head>
<body class="body" id="body">
    <div class="test1">蓝色</div>
    <div class="test2">红色</div>
    <div id="test3" style="color: blue;">蓝色</div>
</body>
</html>
